Automatic assembling apparatus

ABSTRACT

An automatic assembling apparatus is provided for assembling in sequence at least a first component and a second component to an article at an assembling station. The assembling apparatus comprises a first assembling jig for the first assembling component and a second assembling jig for the second component. An annular rail has the first and second assembling jigs mounted thereon such that they are circumferentially movable on the annular rail. The annular rail has a movable rail portion positioned opposite the assembling station which is movable to advance toward and retract from the assembling station. At least one supplying station is positioned with respect to the circumference of the annular rail for supplying components to the assembling jigs at the supplying station. Each of the assembling jigs and a corresponding component are positioned in sequence on the movable rail portion such that the advance movement of the movable rail portion moves the assembling jigs to an assembling position at the assembling station for sequentially carrying out the assembly of each component to the article.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an automatic assembling apparatus wherein atleast two different components are assembled in sequence onto an articleat an assembling station.

2. Description of the Prior Art

Generally in the prior art, a single type of component is assembled ateach station on an assembly line for conveying an article to beassembled.

One type of prior art apparatus is disclosed in Kokai Publication No.Sho 54-47182 of Japanese Unexamined Patent Application. In the devicedisclosed therein, an assembling jig is provided with a holding devicefor a component and a nut runner is movable between a supplying positionon the side of the assembling station, that supplies the component andan assembling position on the assembling station side. The component maythus be supplied to the assembling jig at the supplying position, andmay then be assembled into an article at the assembling position.

With the foregoing type of apparatus, however, there is a problemwherein the assembly line has to be provided with a large number ofassembling stations, resulting in an increase in the length of theassembly line.

When assembling two or more kinds of components at a single assemblingstation, an assembling jig can be provided with plural holding devices.However, this type of apparatus cannot be used when two or more kinds ofcomponents cannot be assembled simultaneously in view of the directionof assembling thereof, the order of assembling or the like.

SUMMARY OF THE INVENTION

It is the object of the present invention to provide an apparatuswherein two or more types of components can be assembled in sequence, ata high efficiency, to an article at a single assembling station.

The present invention is directed to an automatic assembling apparatusfor assembling in sequence at least a first component and a secondcomponent to an article at an assembling station. The assemblingapparatus comprises a first assembling jig for the first assemblingcomponent and a second assembling jig for the second component. Anannular rail has the first and second assembling jigs mounted thereonsuch that they are circumferentially movable on the annular rail. Theannular rail has a movable rail portion positioned opposite theassembling station which is movable to advance toward and retract fromthe assembling station. At least one supplying station is positionedwith respect to the circumference of the annular rail for supplyingcomponents to the assembling jigs at the supplying station. Each of theassembling jigs and a corresponding component are positioned in sequenceon the movable rail portion such that the advance movement of themovable rail portion moves the assembling jigs to an assembling positionat the assembling station for sequentially carrying out the assembly ofeach component to the article.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a sectional view taken along the line IV--IV in FIG. 2;

FIGS. 5 and 6 are sectional views taken along the line V--V and VI--VIin FIG. 4;

FIG. 7 is a sectional view taken along the line VII--VII in FIG. 2;

FIG. 8 is a top plan of a diagram showing a layout of an apparatus forassembling of six kinds of components; and

FIG. 9 is a top plan of a diagram showing a modified embodiment thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An example of a device to be assembled is an air cleaner W₁ which is afirst component and a head cover W₂ which is a second component whichare to be assembled in sequence onto an engine E which is the article.

Referring to FIGS. 1 and 2, an assembly line 1 conveys the engine E on apallet 2. An assembling apparatus 5 is provided on the side of anassembling station A on the assembly line 1 with a first assembling jig3₁ for the air cleaner W₁ and a second assembling jig 3₂ for the headcover W₂. The assembling jigs 3₁ and 3₂ are mounted on an annular rail 4so as to be movable circumferentially along on the annular rail 4. Theportion of the annular rail 4 that is opposite to the assembling stationA is formed with a movable rail 4a which is movable to advance towardand retract from the assembling station A, and the assembling jigs 3₁and 3₂ are arranged such that each may be moved on the movable rail 4a,and additionally may then be moved to an assembling position at theassembling station A by the advance movement of the movable rail 4a.

In more detail, the assembling apparatus 5 is constructed, as shown inFIGS. 2 and 3. The apparatus 5 comprises a machine base 6 and a slidetable 7 which is movable to advance towards the assembling station A andretract therefrom along on a pair of guide rails 7a fixed on the machinebase 6. A stationary base 8 is located above the slide table 7 and isfixed through leg members 8a to the machine base 6. As shown in FIGS. 4and 5, a stationary rail 4b which is a portion, of the annular rail 4 isformed by a pair of upper and lower rails which are attached to thestationary base 8. The movable rail 4a is also formed of a pair of upperand lower rails which are attached to the slide table 7. The slide table7 is provided on its lower surface with a screw rod 7c which extendsalong an X axis, that is, in the advancing and retracting direction ofthe table 7, as shown in FIG. 2. The rod 7c is in threaded engagementwith a nut sleeve 7b on the machine base 6, and the slide table 7 isprovided on its rear end portion with a servomotor 7e for rotating thescrew rod 7c in the forward and reverse directions, through a belt 7d,as shown in FIG. 3.

Thus, by the forward and reverse rotations of the screw rod 7c by themotor 7e, the slide table 7 may be advanced and retracted in the X axialdirection, and if the slide table 7 is retracted, the movable rail 4a isbrought into alignment with the stationary rail 4b to form the annularrail 4. Thus, it is possible to move the assembling jig 3₁ and 3₂ aroundalong on the annular rail 4 including the movable rail 4a.

Each of the assembling jigs 3₁ and 3₂ has a main body 3a provided with acomponent holding device and a nut runner supported on a supportingframe 3b provided on the rear portion thereof. The main body 3a isswingable about a shaft 3d by means of a cylinder 3c between adownwardly turned vertical orientation and a forwardly turned horizontalorientation. Each of the assembling jigs 3₁ and 3₂ are supported on theannular rail 4 by a pair of guide rollers 3f provided on a bracket 3eattached to a rear wall of the supporting frame 3b, as shown in FIG. 5.Additionally, an index means 9 is provided on the stationary base 8 formoving the assembling jigs 3₁ and 3₂ circumferentially along the annularrail 4.

The index means 9, as shown in FIG. 5, includes an index member 9chaving plural index arms 9b disposed radially and is rotatably supportedon the outer circumference of a lower end portion of a supporting column9a positioned on the stationary base 8 at the center of the annular rail4. The member 9c is rotated through a belt 9f, a reduction gear 9g and agear 9h, by a servomotor 9e mounted on machine frame 9d fixed to thesupporting column 9a.

As shown in FIGS. 4 and 6, an engaging member 3g projecting from therear wall of the-supporting frame 3b of each of the assembling jigs 3₁and 3₂, is engageable with a forward end of each index arm 9b and ismoved into and out of engagement in the radial direction. By turning ofthe index member 9, the assembling jigs 3₁ and 3₂ may be given mutuallysynchronized movement in the circumferential direction of the annularrail 4. When the movable rail 4a is moved forward when an assembling jig3₁ or 3₂ is selected, the engaging member 3g comes out of engagementwith the index arm 9b. In order that, at that time, the assembling jig3₁ or 3₂ is held stationary in relation to the movable rail 4a, aforward end portion of the slide table 7 is provided, with a dockingcylinder 10 which is engageable with each assembling jig 3₁ and 3₂.

A pipe joint member 11 is attached to a forward end of each index arm9b, and branch pipes 12a diverge from a circular manifold 12, which isrotatably supported on an upper end portion of the supporting column 9a.The branch pipes 12a are connected to each joint member 11, and aflexible pipe 11a, connected to each diverged pipe 12a, extends fromeach joint 11. Each flexible pipe 11a is connected to each assemblingjig 3₁ and 3₂, and an external air source is connected to a supply pipe12b provided at the center of the manifold 12 as shown in FIG. 2. Inthis manner, each assembling jig 3₁ and 3₂ may be provided with air foroperating a holding device, the nut runner and the cylinder 3c thereof.Additionally, cables for supplying electric power to each of theservomotors 7e and 9e are inserted through a pipe 12c mounted on aninner circumferential surface of the pipe 12b.

Supplying stations B₁ and B₂ for supplying the air cleaner W₁ and thehead cover W₂, respectively, are provided outside of the circumferenceof the annular rail 4. In the illustrated example, a first supplyingstation B₁ for supplying the air cleaner W₁ which is to be assembled tothe engine E first, is disposed at a position which is outside andopposite to the movable rail 4a, that is, at a front position which isin front of the annular rail 4. A second supplying station B₂ forsupplying the head cover W₂ is disposed at a rear position which isoutside and to the rear of the annular rail 4. The first assembling jig3₁ and the second assembling jig 3₂ are mounted on opposite sides of theannular rail 4 180 degrees out of phase in the circumferentialdirection, such that when the first assembling jig 3₁ is selected to bepositioned on the movable rail 4a by the index means 9, the secondassembling jig 3₂ is moved to a position that is coincident with thesecond supplying station B₂.

The respective supplying stations B₁ and B₂ are arranged such that theair cleaner W₁ set with bolts, and the head cover W₂ set with bolts, aresupplied thereto on pallets 13₁ and 13₂ through respective conveyingpassages 14₁ and 14₂ such that when the respective pallets 13₁ and 13₂are lifted by lifters 15₁ and 15₂ provided at the respective supplyingstations B₁ and B₂, the air cleaner W₁ and the head cover W₂ on therespective pallets 13₁ and 13₂ are transferred to the respectiveassembling jigs 3₁ and 3₂, together with the bolts. The pallets 13₁ and13₂ which are then empty, are then returned to respective predeterminedset stations (not shown) through pallet returning passages 16₁ and 16₂provided above the respective conveying passages 14₁ and 14₂.

Each lifter 15₁ and 15₂ as shown in FIGS. 1 and 7, comprises a forkmember 15a for supporting each pallet 13₁ and 13₂ and is movable upwardsand downwards along guide rails 15d, on the sides thereof by the upwardand downward swing movements of a swingable arm 15c positioned to bemoved by a servomotor 15b. Additionally, receiving frames 17 each havinga row of plural rollers 17a aligned in an inclined arrangement, receivethe side edge portions of a lower surface of each pallet 13₁ and 13₂. Asshown in FIG. 2, the receiving frames 17 are provided on both sides ofeach supplying station B₁ and B₂ and are movable to swing about a shaft17b provided on a lower end portion thereof between an upwardly raisedposition and an outwardly lowered position. Thus, after each pallet 13₁and 13₂ is lifted to a predetermined elevated position by the upwardmovement of the fork member 15a, the two receiving frames 17 are raised,and in this condition, if the fork member 15a is moved downwards, theneach pallet 13₁ and 13₂ may be supported by a roller group 17a, and maybe discharged to each pallet returning passage 16₁ and 16₂ due to theinclination thereof.

Belt conveyors 14a and 16a are provided in each of the conveyingpassages 14₁ and 14₂ and each of the returning passages 16₁ and 16₂, andan elevating frame 14b is provided at a corner portion of the firstconveying passage 14₁. The elevating frame 14b and the belt conveyers14a, cross at right angles with each other as shown in FIG. 7, and a rowof plural rollers 14c are provided on each side portion of the elevatingframe 14b and are inclined downwards towards the belt conveyer 14aextending towards the first supplying station B₁. Thus, the upwardmovement of the elevating frame 14b supports the pallet 13₁ on theroller group 14c in an inclined manner for transfer to the belt conveyer14a.

Next, the operation of the foregoing embodiment will be explained asfollows:

During conveying of the engine E, the first assembling jig 3₁ isselected to be positioned on the movable rail 4a, and the jig main body3a thereof is swung downwards to take its vertical orientation.Meanwhile, the pallet 13₁ supplied to the first supplying station B₁ islifted by the lifter 15₁, and the air cleaner W₁ and the bolts on thepallet 13₁ are held by a holding device provided on the jig main body3a. Thereafter, the empty pallet 13₁ is discharged to the palletreturning passage 16₁ and the jig main body 3a is swung to take itshorizontal orientation. Thus, the transferring operation of the aircleaner W₁ to the first assembling jig 3₁ is completed.

After the engine E is conveyed into the assembling station A and is setin a predetermined position, the first assembling jig 3₁ is moved to anassembling position of the assembling station A by the advancing orforward movement of the movable rail 4a, and the air cleaner W₁ isbolted to the engine E by operation of the nut runner.

During the transferring operation or the assembling operation of the aircleaner W₁ as described above, in almost the same manner as in theforegoing transferring operation, the second assembling jig 3₂ locatedat a circumferential position facing the second supplying station B₂ issupplied with the head cover W₂ on a pallet 13₂ from the secondsupplying station B₂.

After the completion of assembling of the air cleaner W₁ to the engineE, the movable rail 4a is retracted or moved backwards and thereafter,the first and second assembling jigs 3₁ and 3₂ are movedcircumferentially on the annular rail 4 by 180 degrees, so that thesecond assembling jig 3₂ is selected on the movable rail 4a, and theengine E is turned manually or automatically by 90 degrees such that itscylinder head is directed toward the X axis direction. Thereafter, themovable rail 4a is advanced, and thereby the second assembling jig 3₂ ismoved to the assembling position with the jig main body 3a thereof inits horizontal orientation, and the head cover W₂ is bolted to thecylinder head of the engine E. The engine E thus assembled is thenconveyed from the assembling station A, and the next engine E to beassembled is conveyed into the assembling station. During this conveyingoperation, the first and second assembling jigs 3₁ and 3₂ are againmoved circumferentially on the annular rail 4 by 180 degrees, such thatthe first assembling jig 3₁ is selected on the movable rail 4a.

By repeating the foregoing procedures, the assembling of the air cleanerW₁ and that of the head cover W₂ to the engine E are carried out insequence.

Thus, according to the foregoing example, when the first assembling jig3₁ is selected on the movable rail 4a, the air cleaner W₁ can betransferred thereto, and immediately after the engine E is conveyed intothe assembling station A and is set in position, the movable rail 4a isadvanced to assemble the air cleaner W₁ to the engine E andadditionally, before the completion of assembling of the air cleaner W₁thereto, the head cover W₂ can be transferred to the second assemblingjig 3₂, and as a result, the assembling of the head cover W₂ to theengine E can be carried out without loss of time required fortransferring of the head cover W₂ after the assembling of the aircleaner W₁. Thus, the workability can be improved.

In the foregoing embodiment, six assembling jigs may be mountedcircumferentially on the annular rail 4 at an interval of 60 degrees.If, in this case, as shown in FIG. 4, the first and second assemblingjigs 3₁ and 3₂ are for a first type of engine, first and secondassembling jigs 3₁ ' and 3₂ ' for a second type of engine, and furtheradditional first and second assembling jigs 3₁ " and 3₂ " for a thirdtype of engine may be mounted on the annular rail 4. This isadvantageous because the assembling apparatus can comply with change ina type of an engine E to be assembled.

Further, by using the foregoing assembling apparatus 5, six kinds ofassembling members W₁, W₂ . . . W₆ can be assembled to an article. FIG.8 shows one embodiment thereof. This embodiment has an arrangement suchthat a first supplying station B₁ for a first assembling member W₁ whichis to be assembled first is provided at a circumferential position ofthe movable rail 4a, and with the station B₁ being a starting point, thesecond to sixth supplying stations B₂ . . . B₆ for second to sixthassembling members W₂ . . . W₆ being disposed, in accordance with theassembling sequence thereof, around the annular rail 4 atcircumferentially spaced positions at an interval of 60 degrees. Therespective supplying stations B₁, B₂ . . . B₆ are arranged to besupplied with the respective components W₁, W₂ . . . W₆ throughrespective conveying passages 14₁, 14₂ . . . 14₆, and further it isarranged such that, when the first assembling jig 3₁ for the firstcomponents W₁ is selected on the movable rail 4a, the second to sixthassembling jigs 3₂ . . . 3₆ for the second to sixth components W₂ . . .W₆ are moved to respective stations which correspond to the second tosixth supplying stations B₂ . . . B₆. Thus, prior to completion ofassembling of the first components W₁ by the first assembling jig 31,the second to sixth assembling jigs 3₂ . . . 3₆ are transferred to thesecond to sixth components W₂ . . . W₆, and thereafter the second tosixth assembling jigs 3₂ . . . 3₆ may be selected one after another onthe movable rail 4a for effecting the sequential assembling of thesecond to sixth components W₂ . . . W₆.

In another embodiment shown in FIG. 9, a single supplying station B isprovided to correspond to a circumferential position which iscircumferentially displaced from the movable rail 4a by 60 degrees, andfirst to sixth components W₁ . . . W₆ are supplied one after another tostation B through a conveying passage 14. With this arrangement, firstthe first component W₁ is transferred to the first assembling jig 3₁ atthe supplying station B, and thereafter the first assembling jig 3₁ ismoved onto the movable rail 4a and the component W₁ is assembled to thearticle. During this operation, the second component W₂ is transferredto the second assembling jig 3₂ at the station B, and the secondassembling jig 3₂ is then selected on the movable rail 4a, and theassembling of the second component W₂ to the article and thetransferring of the third component W₃ to the third assembling jig 3₃ atthe station B are carried out at the same time. Thereafter, by nearlythe same operations, assembling of the components and transferring ofthe next component are effected in sequence.

Thus, according to this invention, two or more kinds of components canbe assembled to an article in sequence with high efficiency at a singleassembling station, and the assembly line can be decreased in length andthe installation cost for the apparatus can be lowered.

We claim:
 1. An automatic assembling apparatus for assembling, insequence, at least a first component and a second component to anarticle at an assembling station, said assembling apparatus comprising afirst assembling jig for said first component and a second assemblingjig for said second component; an annular rail means wherein said firstand second assembling jigs are mounted on and circumferentially movableon said annular rail means; said annular rail means having an annularmovable rail portion positioned opposite said assembling station whichis movable to advance toward and retract from said assembling station;at least one supplying station positioned with respect to thecircumference of said annular rail means for supplying components tosaid assembling jigs at said supplying station; wherein each of saidassembling jigs and a corresponding component are positioned in sequenceon said movable rail portion and, wherein the advance movement of themovable rail portion moves said assembling jigs to an assemblingposition at said assembling station for sequentially carrying out theassembly of each component to the article.
 2. An automatic assemblingapparatus as claimed in claim 1, wherein said at least one supplyingstation comprises a plurality of supplying stations, each supplyingstation supplying a corresponding component, wherein a first supplyingstation supplies said first component, which is to be the firstcomponent assembled to the article, at a circumferential position thatis opposite to said movable rail portion such that when said firstassembling jig for said first component is selected on said movable railportion, a second assembling jig for said second component is moved tocircumferential position that is opposite to a second supplying stationfor supplying said second component.
 3. An automatic assemblingapparatus as claimed in claim 1, wherein said at least one supplyingstation is a single supplying station positioned at a circumferentialposition not opposite to said movable rail portion, and wherein saidcomponents are supplied to said supplying station in accordance with theorder of assembly thereof, whereby when an assembling jig is selected onsaid movable rail portion, said assembling jig for said component to benext assembled is moved to a position which is opposite to saidsupplying station.
 4. An automatic assembling apparatus as claimed inclaim 1, including a machine base, slide table means mounted on saidmachine base, and a stationary base means, wherein said movable railportion is mounted on said slide table means, said slide table meansbeing movable to advance and retract with respect to said assemblingstation and wherein said rail means includes a stationary rail portion,said stationary rail portion being mounted on said stationary basemeans.
 5. An automatic assembling apparatus as claimed in claim 4,including indexing means, said assembling jigs being operatively coupledto said indexing means, wherein said indexing means moves saidassembling jigs circumferentially around said rail means.